Process for direct conversion of methane into acetic acid

Abstract

The invention consists on the utilization of complexes of vanadium (in the +4 and +5 oxidation states) with bi- or poly-dentate ligands coordinated by nitrogen and oxygen (N,O) or by oxygen and oxygen (O,O) atoms, namely derivatives of aminoalcohols, (hydroxyimino)dicarboxylic acids, hydroxypyranones, trifluoroacetic acid, triflic acid or inorganic acid, as catalysts for the direct single-pot conversion, under mild conditions, of methane in acetic acid, either in the absence or in the presence of carbon monoxide, and in the presence of a peroxodisulfate salt (K2S2O8), in trifluoroacetic acid (CF3COOH), according to the general reaction (I).

1. A process for the direct one-pot conversion of methane into acetic acid, comprising combining methane with a catalytic system comprising a vanadium complex, a peroxodisulfate salt and trifluoroacetic acid, and reacting methane with the catalytic system in the pot under mild reaction conditions, in the substantial absence of carbon monoxide. 
     
     
       2. The process of  claim 1 , wherein the vanadium complex comprises vanadium in the +4 or +5 oxidation state with one or more ligands selected from the group consisting of di- and poly-dentate ligands, coordinated by nitrogen and oxygen atoms, or by oxygen atoms, wherein said ligands are derived from aminoalcohols, (hydroxyimino)dicarboxylic acids, hydroxypyrones, trifluoroacetic acid, triflic acid or acetylacetone. 
     
     
       3. The process of  claim 2 , wherein said ligands are derived from acetylacetonate. 
     
     
       4. A process for the direct one-pot conversion of methane into acetic acid, comprising combining methane with a catalytic system comprising a vanadium complex, a peroxodisulfate salt and trifluoroacetic acid, and reacting methane with the catalytic system in the pot under mild reaction conditions, in the presence of carbon monoxide, wherein the vanadium complex comprises vanadium in the +4 or +5 oxidation state with one or more ligands selected from the group consisting of di- and poly-dentate ligands, coordinated by nitrogen and oxygen atoms, or by oxygen atoms, wherein said ligands are derived from aminoalcohols, (hydroxyimino)dicarboxylic acids, hydroxypyrones, trifluoroacetic acid or triflic acid.